Aromatic amino compounds such as aniline and toluene-diamine (TDA) are produced commercially by the catalytic hydrogenation of mononitrobenzene (MNB) and dinitrotoluene (DNT), respectively. These reactions are performed in methanol solution and are generally catalyzed by Raney nickel (Canadian Pat. No. 774,564). These processes necessitate the separation and recovery of the Raney nickel. It is also known to use noble metal catalysts (Canadian Pat. No. 705,911). Rhodium catalysts in the form of granules, sponge, pellets and chunks are also known (Canadian Pat. No. 712,193).
The instant invention overcomes the operation and maintenance costs of the equipment necessary for Raney nickel separation and recovery by the use of fixed bed noble metal catalysts.